Tungsten alloy



Patented Sept. 18, 1923.

1m AR PACZ, or summer, one, assumes no GENERAL nnncmmc comm CORPORATION on NEW YO runes'rm ALLOY.

K Drawing. Application filed January 15, 19%, Serial No. 851,684. Renewed January 24, 1938.

' To all whom it may concern:

Be it known that I, ALADAB PACZ, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State a of Ohio, have invented a new and useful Tungsten Alloy, of which the following is a ter beingfpresent in a comparatively small proportion, exceptionally good results are secured especially when the metal is used for filaments for incandescent lamps.

, According produce the alloy or mixture of tungsten and silicon by first intimately mixing the tung- 20 sten with silicic acid and then reducing'the latter. One method which may be followed 'is to mix about 5 grams of powdered magnesium with about 300 28 finely divided silicic acid. In my application Serial Number 149,915, filed Feb.' 20, 1917, I have described a method of preparing tungsten which includes the prellminary preparation of finely divided tungsten.

intnnately mixed with silicic acid and which is used in theproduction of the socalled 218 metal. That mixture of tun sten and silicic acid may-be utilized to ad vantage in the present instance. The mixture thus produced may be passed through a highly eatedfurnace, for instance; an

- electrically heated furnace, the magnesium reducing the silicic acid t0' f QI.II1 metallicsilicon intimately incorporated with the 0 tungsten powder. The magnesium oxide which forms in the re-action may then be dissolved out by hydrochloric acid leaving only the mixture of the tungsten and the s licon. If preferred, the reduction may be made of tungstic acid mixed with silicic acid, the tungstic acidbeing reduced by hydrogen and the silicic acid by magnesium.

e mixture of tungsten and silicon is pressed into slugs, formed and otherwise 0 mechanic It is my scribed method, an alloy or composite metal to my invention, I prefer-to;-

ams of finely dividedtungsten mixed with about 6 gramsof with which is A intimately similar devices which consists in ally treated and drawn into wire as described in the Coolidge Patent No.

theory that by the :above dew of tungsten and silicon is produced in which the silicon is dissolved 1n the tung-' sten and the silicon is not volatilized out to the extent that silica is volatilized in the regular 218 process described in the aforesaid application.

Incandescent lamp filaments produced from the combination of tungsten and silicon'possesses in a high degree, non-sagging qualities like those of the 218 wire and, moreover, do not interlock when the lamp is subjected to shock such as in a bump test. This makes this wire especially suitable for straight filaments although it is also useful for coiled filaments.

The percentages of silicon may vary somewhat but-a comparatively small quantity is all that is necessary and I have found that between 1 and 3 per cent silicon in the metal before forming, gives the best results.

What I claim and desire to secure by Letters Patent of the United States is 1. A drawn metal filament for electric incandescent lamps consisting of tungsten incorporated a small percentage of'silicon.

2.. A drawn wire consisting of tungsten with which is intimately incorporated a" small ercentage of silicon.

3. T e process of producing wire suitable for electric incandescent lamp filaments and similar devices,'which consists in heating to material, silicic acid and magnesium, pressing the resultant metal into slugs and then heatin and mechanicall working the same. 5. 0 process of producing wire suitable for electric incandescent lamp filaments and pressing into slu finely divided tungsten havin silicon intimately incorporated therewith and then sintering and mechanically workm the same.

n witness whereof I have hereunto set 'my hand this 26th day of ecember 1919. 

